Siemens SINUMERIK 828D Function Manual

Also see for SINUMERIK 828D Turning: Diagnostic manual Function manual Equipment manual Programming manual Operating manual

Contents

B1: Continuouspath Mode, Exact Stop, LookAhead3.6 Contour/Orientation toleranceBasic Functions204 Function Manual, 09/2011, 6FC5397-0BP40-2BA0Programming does not trigger a preprocessing stop. If possible, it does not interrupt NC block compressioneither.The programmed values are valid until they are reprogrammed or deleted by being written with a negative value.They are also deleted at the end of a program, in the event of a channel reset, a mode group reset, an NCK reset(warm restart), and POWER ON (cold restart). On deletion of these values, the values from the machine andsetting data are restored.New values can be programmed and become effective in any block.Read tolerance valuesFor more advanced applications or for diagnostics, the currently valid tolerances for the compressor functions(COMPON, COMPCURV, COMPCAD), the smoothing types G642, G643, G645, OST, and the orientationsmoothing ORISON can be read via system variables irrespective of how they might have come about.• For the display in the user interface, in synchronized actions or with a preprocessing stop in the part programvia the system variables:NoteThe programmed tolerance also acts upon functions which are only implicitly dependentupon the tolerance. These are currently:• Limiting the chord error in the setpoint value calculation• The basic functions of the free-form surface modeNoteThe following rounding functions are not affected by the programming of CTOL, OTOL, andATOL:• rounding orientation with OSDReason: OSD does not use a tolerance, it uses a distance from the block transition.• Rounding with G644Reason: G644 is not used for processing, it is used for optimizing tool changes and othermovements in air.• Rounding block transitions with uniform tangents and non-uniform curvature with G645G645 virtually always behaves like G642 and, thus, uses the programmed tolerances.The tolerance value from machine data MD33120 $MA_PATH_TRANS_POS_TOL is onlyused in uniformly tangential block transitions with a jump in curvature, e.g. a tangentialcircle/straight line transition. The rounding path at these points may also be locatedoutside the programmed contour, where many applications are less tolerant.Furthermore, it generally takes a small, fixed tolerance to compensate for the sort ofchanges in curvature which need not concern the NC programmer.